Spine morphology and energetics: how principles from nature apply to robotics

Inspired by the locomotive advantages that an articulated spine enables in quadrupedal animals, we
explore and quantify the energetic effect that an articulated spine has in legged robots. We compare
two model instances of a conceptual planar quadruped: one with a traditional rigid main body and one
with an articulated main body with an actuated spinal joint. Both models feature four distinct legs,
series elastic actuation, distributed mass in all body segments, and limits on actuator torque and
speed. Using optimal control to find the energetically optimal joint trajectories, actuator inputs,
and footfall timing, we examine and compare the positive mechanical work cost of transport of both
models across multiple gaits and speeds. Our results show that an articulated spine increases the
maximum possible speed and improves the locomotor economy at higher velocities, especially for
asymmetrical gaits. The driving factors for these improvements are the same mechanistic effects
that...

Source: Bioinspiration and Biomimetics - March 14, 2018 Category: Science Authors: Yevgeniy Yesilevskiy, William Yang and C David Remy Source Type: research